var createError = require('http-errors');
var express = require('express');
var path = require('path');
var cookieParser = require('cookie-parser');
var logger = require('morgan');

require('./db/mondb');
require('./db/classModel');
require('./db/courseModel');
require('./db/student');
require('./db/teacherModels');



var app = express();

// 设置 CORS 允许跨域
var allowCrossDomain = function(req, res, next) {
    // 设置允许哪一个源（域）可以进行跨域访问，* 表示所有源
    res.header("Access-Control-Allow-Origin", "*");
    // 设置允许跨域访问的请求头
    res.header("Access-Control-Allow-Headers", "X-Requested-With,Origin,Content-Type,Accept,Authorization");
    // 设置允许跨域访问的请求类型
    res.header("Access-Control-Allow-Methods", "PUT,POST,GET,DELETE");
    // 设置允许 cookie 发送到服务器 
    res.header('Access-Control-Allow-Credentials', 'true');
    next();
};



// view engine setup
app.set('views', path.join(__dirname, 'views'));
app.set('view engine', 'jade');

app.use(logger('dev'));
app.use(express.json());
app.use(express.urlencoded({ extended: false }));
app.use(cookieParser());
app.use(express.static(path.join(__dirname, 'public')));



// catch 404 and forward to error handler
app.use(function(req, res, next) {
    next(createError(404));
});

// error handler
app.use(function(err, req, res, next) {
    // set locals, only providing error in development
    res.locals.message = err.message;
    res.locals.error = req.app.get('env') === 'development' ? err : {};

    // render the error page
    res.status(err.status || 500);
    res.render('error');
});

// module.exports = app;
app.listen(3000, function() {
    console.log('服务器启动成功，端口号为3000');
})